Cooling recovery system and method

Abstract

A cooling recover system and method are disclosed. A fluid, such as water, is chilled and provided to a cooling coil to cool and dehumidify air passing over the cooling coil. The fluid is output from the cooling coil through an outlet, and at least a portion of the fluid from the outlet of the cooling coil is provided to an inlet of a heat transfer coil to reheat air passing over the heat transfer coil. The fluid is warmed as it passes through the cooling coil, which warmer temperature serves to reheat the air passing over the heat transfer coil.

What is claimed: 
     
       1. An air conditioning system comprising
 a cooling coil having an inlet to receive chilled liquid water at a first temperature from a fluid chiller to cool and dehumidify air that passes over the cooling coil, and having an outlet to output spent chilled liquid water at a second temperature, the second temperature being greater than the first temperature due to heat exchange from the air to the chilled water; 
 a fluid recovery conduit to receive the spent chilled liquid water from the outlet of the cooling coil; and 
 a heating coil having an inlet to receive the spent chilled liquid water, the heating coil configured to cause heat exchange from the spent chilled fluid to the air previously passed over and cooled and dehumidified by the cooling coil as that air passes over the heating coil, the heat exchange caused by the heating coil resulting in cooling of the spent chilled liquid water to a third temperature before the spent chilled liquid water is returned to the fluid chiller, the third temperature being lower than the second temperature, further comprising a control system configured to control a plurality of control valves such that: operation of the cooling coil results in the air passing over the cooling coil achieving a supply air temperature sufficiently low to cause dehumidification while raising the second temperature of the spent cooled liquid water into a range of approximately 65° F. to 75° F. (approximately 18° C. to 25° C.); and operation of the heating coil results in the air passing over the heating coil being reheated to conform to occupant or process cooling loads while a cooling demand on the fluid chiller is reduced relative to the spent chilled liquid water at the second temperature. 
 
     
     
       2. An air conditioning system in accordance with  claim 1 , wherein the fluid chiller includes one or more cooling plants. 
     
     
       3. An air conditioning system in accordance with  claim 1 , further comprising one or more flow valves to selectively modulate a flow of the spent chilled liquid water through the fluid recovery conduit. 
     
     
       4. An air conditioning system in accordance with  claim 3 , wherein the fluid recovery conduit further includes a fluid pumping system to provide the flow of the spent chilled liquid water. 
     
     
       5. An air conditioning system in accordance with  claim 1 , further comprising one or more fans for pushing the air that passes over the cooling coil and heating coil. 
     
     
       6. A method for conditioning air, the method comprising:
 chilling a fluid; 
 providing the chilled fluid comprising chilled liquid water at a first temperature to a cooling coil to cool and dehumidify air passing over the cooling coil; 
 outputting spent chilled water from the cooling coil through an outlet at a second temperature, the second temperature being greater than the first temperature due to heat exchange from the air to the chilled water; and 
 providing at least a portion of the spent chilled water from the outlet of the cooling coil to an inlet of a heating coil, the heating coil configured to cause heat exchange from the spent chilled fluid to the air previously passed over and cooled and dehumidified by the cooling coil as that air passes over the heating coil, the heat exchange caused by the heating coil resulting in cooling of the spent chilled water to a third temperature before the spent chilled water is returned to the fluid chiller, the third temperature being lower than the second temperature, further comprising controlling a plurality of control valves such that: operation of the cooling coil results in the air passing over the cooling coil achieving a supply air temperature sufficiently low to cause dehumidification while raising the second temperature into a range of approximately 65° F. to 75° F. (approximately 18° C. to 25° C.); and operation of the heating coil results in the air passing over the heating coil being reheated to conform to occupant or process cooling loads while a cooling demand on the fluid chiller is reduced relative to water at the second temperature. 
 
     
     
       7. A method in accordance with  claim 6 , further comprising selectively modulating a flow of the spent chilled liquid water from the outlet of the cooling coil to the inlet of the heating coil. 
     
     
       8. A method in accordance with  claim 6 , wherein the chilled liquid water is chilled by passing liquid water through a fluid chiller prior to providing the chilled liquid water to the cooling coil. 
     
     
       9. An air conditioning system comprising:
 a heating coil having an inlet to receive spent chilled liquid water at a second temperature via a fluid recovery conduit connected to an outlet of a cooling coil, the heating coil reheating, with the spent chilled liquid water, air that has been cooled and dehumidified by the cooling coil, the cooling coil receiving chilled liquid water from a fluid chiller such that the air passing over the cooling coil has been cooled and dehumidified prior to reaching the heating coil, further comprising a control system configured to control a plurality of control valves such that: operation of the cooling coil results in the air passing over the cooling coil achieving a supply air temperature sufficiently low to cause dehumidification while raising the second temperature into a range of approximately 65° F. to 75° F. (approximately 18° C. to 25° C.); and operation of the heating coil results in the air passing over the heating coil being reheated to conform to occupant or process cooling loads while a cooling demand on the fluid chiller is reduced relative to water at the second temperature. 
 
     
     
       10. An air conditioning system in accordance with  claim 9 , wherein the fluid recovery conduit includes piping. 
     
     
       11. An air conditioning system in accordance with  claim 9 , wherein the chilled liquid water is chilled prior to the chilled liquid water flowing through the cooling coil such that the chilled liquid water is delivered to the cooling coil at first temperature which is lower than the second temperature at which the spent chilled liquid water is outputted from the cooling coil due to heat exchange from the air to the chilled water in the cooling coil. 
     
     
       12. A method for conditioning air, the method comprising:
 receiving, through a fluid recovery conduit connected to an outlet of a cooling coil, spent chilled liquid water at a heating coil, the spent chilled liquid water being warmed as it flows through the cooling coil due to air passing over the cooling coil and being cooled and dehumidified, the spent chilled water being output from the cooling coil at a second temperature; and 
 reheating, with the heating coil, the air that has been cooled and dehumidified by the cooling coil, the heating coil configured to cause heat exchange from the spent chilled fluid to the air, the heat exchange caused by the heating coil resulting in cooling of the spent chilled water to a third temperature before the spent chilled water is returned to a fluid chiller, the third temperature being lower than the second temperature, further comprising controlling a plurality of control valves such that: operation of the cooling coil results in the air passing over the cooling coil achieving a supply air temperature sufficiently low to cause dehumidification while raising the second temperature into a range of approximately 65° F. to 75° F. (approximately 18° C. to 25° C.); and operation of the heating coil results in the air passing over the heating coil being reheated to conform to occupant or process cooling loads while a cooling demand on the fluid chiller is reduced relative to water at the second temperature. 
 
     
     
       13. A method in accordance with  claim 12 , chilling the chilled liquid water prior to the chilled liquid water flowing through the cooling coil such that the chilled liquid water is delivered to the cooling coil at first temperature which is lower than the second temperature at which the spent chilled liquid water is outputted from the cooling coil due to heat exchange from the air to the chilled water in the cooling coil. 
     
     
       14. A method in accordance with  claim 12 , further comprising blowing the air over the cooling coil and the heating coil. 
     
     
       15. A method in accordance with  claim 12 , further comprising providing, to conduits in a structure, air that has been reheated by the heating coil. 
     
     
       16. A method in accordance with  claim 12 , further comprising filtering the air of particles. 
     
     
       17. A method in accordance with  claim 12 , further comprising selectively modulating a flow of the spent chilled liquid water from the cooling coil to the heating coil.